Bonnet and stuffing box assembly

ABSTRACT

Example aspects of a bushing assembly for a bonnet and stuffing box assembly, a bonnet and stuffing box assembly, and a method for using a bonnet and stuffing box assembly are disclosed. The bushing assembly for a bonnet and stuffing box assembly can comprise a stuffing box bushing, the stuffing box bushing defining an outer stuffing box bushing surface and a stuffing box bushing bore wall; and a bonnet bushing, the bonnet bushing defining an outer bonnet bushing surface and a bonnet bushing bore wall, the bonnet bushing bore wall and the stuffing box bushing bore wall together defining a bushing bore configured to receive a stem therethrough.

TECHNICAL FIELD

This disclosure relates to the field of stuffing boxes. Morespecifically, this disclosure relates to a bonnet and stuffing boxassembly comprising a bushing assembly.

BACKGROUND

Bonnet and stuffing box assemblies are connected to fluid pipelinesystems, such as municipal water systems, and allow operators to operatea valve, or other device, connected thereto. Bonnet and stuffing boxassemblies can comprise a bonnet, a stuffing box, and a stem. Each ofthe bonnet and the stuffing box can define a stem bore through which thestem can extend. The stem bores typically must be precision-machined foroptimal engagement with the stem. However, precision machining largecomponents like the bonnet and stuffing box can significantly slow downand decrease the efficiency of the manufacturing and assembly processes.Furthermore, various components of the bonnet and stuffing box assemblyoften are formed from materials that are not corrosion-resistant, suchas iron. Such materials can quickly rust. In some instances, rust candevelop even before the assembly of the components due to the slowedmanufacturing timeline. Rust can decrease the functionality and lifespanof the bonnet and stuffing box assembly. Rust can also pose health risksto the public, for example, when introduced into drinking waterapplications.

SUMMARY

It is to be understood that this summary is not an extensive overview ofthe disclosure. This summary is exemplary and not restrictive, and it isintended neither to identify key or critical elements of the disclosurenor delineate the scope thereof. The sole purpose of this summary is toexplain and exemplify certain concepts off the disclosure as anintroduction to the following complete and extensive detaileddescription.

Disclosed is a bushing assembly for a bonnet and stuffing box assembly,the bushing assembly comprising a stuffing box bushing, the stuffing boxbushing defining an outer stuffing box bushing surface and a stuffingbox bushing bore wall; and a bonnet bushing, the bonnet bushing definingan outer bonnet bushing surface and a bonnet bushing bore wall, thebonnet bushing bore wall and the stuffing box bushing bore wall togetherdefining a bushing bore configured to receive a stem therethrough

Also disclosed is a bonnet and stuffing box assembly comprising abonnet, the bonnet defining a bonnet bore; a stuffing box connected tothe bonnet, the stuffing box defining a stuffing box bore, the stuffingbox bore and bonnet bore defining an assembly bore; a bushing assemblyreceived in the assembly bore, the bushing assembly defining a bushingbore; and a stem extending through the bushing bore.

Also disclosed is a method for using a bonnet and stuffing box assemblycomprising providing a stuffing box, a bonnet, a bushing assembly, and astem, the stuffing box and bonnet defining an assembly bore, the bushingassembly received in the assembly bore, the bushing assembly defining abushing bore, and the stem received through the bushing bore; sealingthe stem relative to the bushing assembly to prohibit fluid flow throughthe bushing bore; sealing the bushing bore relative to the bonnet toprohibit fluid flow through the assembly bore; and turning the stemrelative to the bushing assembly, bonnet, and stuffing box to actuate avalve

Various implementations described in the present disclosure may includeadditional systems, methods, features, and advantages, which may notnecessarily be expressly disclosed herein but will be apparent to one ofordinary skill in the art upon examination of the following detaileddescription and accompanying drawings. It is intended that all suchsystems, methods, features, and advantages be included within thepresent disclosure and protected by the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and components of the following figures are illustrated toemphasize the general principles of the present disclosure.Corresponding features and components throughout the figures may bedesignated by matching reference characters for the sake of consistencyand clarity.

FIG. 1 is a front view of a bonnet and stuffing box assembly, inaccordance with one aspect of the present disclosure.

FIG. 2 is a top perspective view of the bonnet and stuffing box assemblyof FIG. 1.

FIG. 3 is a cross-sectional view of the bonnet and stuffing box assemblyof FIG. 1 taken along line 3-3 of FIG. 1.

FIG. 4 is an exploded view of the bonnet and stuffing box assembly ofFIG. 1.

FIG. 5 is a cross-sectional view of the bonnet and stuffing boxassembly, according to another aspect of the present disclosure.

FIG. 6 is a front view of the bonnet and stuffing box assembly,according to another aspect of the present disclosure, wherein a bushingassembly, a bonnet, and a stuffing box are shown in cross-section.

DETAILED DESCRIPTION

The present disclosure can be understood more readily by reference tothe following detailed description, examples, drawings, and claims, andthe previous and following description. However, before the presentdevices, systems, and/or methods are disclosed and described, it is tobe understood that this disclosure is not limited to the specificdevices, systems, and/or methods disclosed unless otherwise specified,and, as such, can, of course, vary. It is also to be understood that theterminology used herein is for the purpose of describing particularaspects only and is not intended to be limiting.

The following description is provided as an enabling teaching of thepresent devices, systems, and/or methods in its best, currently knownaspect. To this end, those skilled in the relevant art will recognizeand appreciate that many changes can be made to the various aspects ofthe present devices, systems, and/or methods described herein, whilestill obtaining the beneficial results of the present disclosure. Itwill also be apparent that some of the desired benefits of the presentdisclosure can be obtained by selecting some of the features of thepresent disclosure without utilizing other features. Accordingly, thosewho work in the art will recognize that many modifications andadaptations to the present disclosure are possible and can even bedesirable in certain circumstances and are a part of the presentdisclosure. Thus, the following description is provided as illustrativeof the principles of the present disclosure and not in limitationthereof.

As used throughout, the singular forms “a,” “an” and “the” includeplural referents unless the context clearly dictates otherwise. Thus,for example, reference to “an element” can include two or more suchelements unless the context indicates otherwise.

Ranges can be expressed herein as from “about” one particular value,and/or to “about” another particular value. When such a range isexpressed, another aspect includes from the one particular value and/orto the other particular value. Similarly, when values are expressed asapproximations, by use of the antecedent “about,” it will be understoodthat the particular value forms another aspect. It will be furtherunderstood that the endpoints of each of the ranges are significant bothin relation to the other endpoint, and independently of the otherendpoint.

For purposes of the current disclosure, a material property or dimensionmeasuring about X or substantially X on a particular measurement scalemeasures within a range between X plus an industry-standard uppertolerance for the specified measurement and X minus an industry-standardlower tolerance for the specified measurement. Because tolerances canvary between different materials, processes and between differentmodels, the tolerance for a particular measurement of a particularcomponent can fall within a range of tolerances.

As used herein, the terms “optional” or “optionally” mean that thesubsequently described event or circumstance can or cannot occur, andthat the description includes instances where said event or circumstanceoccurs and instances where it does not.

The word “or” as used herein means any one member of a particular listand also includes any combination of members of that list. Further, oneshould note that conditional language, such as, among others, “can,”“could,” “might,” or “may,” unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain aspects include, while other aspects do notinclude, certain features, elements and/or steps. Thus, such conditionallanguage is not generally intended to imply that features, elementsand/or steps are in any way required for one or more particular aspectsor that one or more particular aspects necessarily include logic fordeciding, with or without user input or prompting, whether thesefeatures, elements and/or steps are included or are to be performed inany particular aspect.

Disclosed are components that can be used to perform the disclosedmethods and systems. These and other components are disclosed herein,and it is understood that when combinations, subsets, interactions,groups, etc. of these components are disclosed that while specificreference of each various individual and collective combinations andpermutation of these may not be explicitly disclosed, each isspecifically contemplated and described herein, for all methods andsystems. This applies to all aspects of this application including, butnot limited to, steps in disclosed methods. Thus, if there are a varietyof additional steps that can be performed it is understood that each ofthese additional steps can be performed with any specific aspect orcombination of aspects of the disclosed methods.

Disclosed in the present application is a bushing assembly andassociated methods, systems, devices, and various apparatus. Exampleaspects of the bushing assembly can comprise a first bushing and asecond bushing, wherein the first and second bushings defining a bushingbore configured to receive a stem therethrough. Also disclosed in thepresent application is a bonnet and stuffing box assembly and associatedmethods, systems, devices, and various apparatus. Example aspects of thebonnet and stuffing box assembly can comprise a bonnet, a stuffing box,a stem, and a bushing assembly. It would be understood by one of skillin the art that disclosed bushing assembly and the disclosed bonnet andstuffing box assembly are described in but a few exemplary aspects amongmany. No particular terminology or description should be consideredlimiting on the disclosure or the scope of any claims issuing therefrom.

FIG. 1 illustrates a first aspect of a bonnet and stuffing box assembly100 according to the present disclosure. As shown, the bonnet andstuffing box assembly 100 can comprise a bonnet 110, a stuffing box 150,and a stem 160 extending through the bonnet 110 and the stuffing box150. In example aspects, a gap 190 can be defined between the bonnet 110and the stuffing box 150. An actuator, such as an op nut 170 (i.e., anoperating nut), can be coupled to a top end 162 of the stem 160,relative to the orientation shown. The actuator can be configured toactuate the stem 160, as described in further detail below. The stuffingbox 150 can be connected to the bonnet 110 by a fastener, such as one ormore bolts 180 and nuts 182, as shown. In other aspects, the fastener(s)can be screws, welding, clips, adhesives, or any other suitable fastenerknown in the art. Example aspects of the bonnet and stuffing boxassembly 100 can be configured for fluid pipeline systems, such as, forexample, a municipal water system, a sanitary sewer system, an oilpipeline system, or the like.

In example aspects, the bonnet 110 and the stuffing box 150 can bemanufactured by a casting process. In some aspects, the bonnet 110 andstuffing box 150 can be formed from an inherently corrosion-resistantmaterial, such as, for example, bronze or stainless steel, or cancomprise a corrosion-resistant coating, such as, for example ane-coating, which can be applied by an electrophoretic painting process.Corrosion-resistant materials can provide a benefit of preventing rustfrom forming on the components, as rust can decrease the efficiency andfunctionality of the components. Rust can also be dangerous whenintroduced in drinking water applications. Example aspects of the stem160 can similarly be formed from a corrosion-resistant material, such asbronze or stainless steel, or can be coated in a corrosion-resistantcoating. In a particular aspect, the stem can be formed from manganesebronze, and in another particular aspect, the stem can be formed fromsilicon bronze. Furthermore, in example aspects, the material of thestem 160 and/or other components of the bonnet and stuffing box assembly100 can be selected as desired by a customer for an optimal interactionwith the fluid in the fluid pipeline system, dependent upon the fluid'sparticular chemistry.

Referring to FIG. 2, in the present aspect, the stuffing box 150 candefine a pair of fastener openings 252 a,b formed proximate a bottom end254 thereof, relative to the orientation shown, and the bonnet 110 candefine a pair of fastener slots 212 a,b (212 b not shown) proximate atop end 214 thereof, relative to the orientation shown. Each fasteneropening 252 a,b can be aligned with a corresponding fastener slot 212a,b, and one of the bolts 180 (shown in FIG. 1) can be inserted througheach pair of corresponding fastener openings 252 a,b and fastener slots212 a,b. The nut 182 (shown in FIG. 1) can be tightened on thecorresponding bolt 180 to secure the stuffing box 150 to the bonnet 110and to draw the stuffing box 150 towards the bonnet 110. In the presentaspect, the gap 190 (shown in FIG. 1) can remain between the bonnet 110and stuffing box 150 when the nuts 182 are tightened. In other aspects,the bonnet and stuffing box assembly 100 may not comprise the gap 190when the fasteners are tightened.

According to example aspects, the bonnet and stuffing box assembly 100can be configured to be coupled to equipment (not shown) related to afluid pipeline system. For example, the bonnet and stuffing box assembly100 can be configured to couple a valve, such as a gate valve, butterflyvalve, check valve, or any other suitable equipment associated with afluid pipeline system. As shown in FIG. 2, the bonnet 110 can define oneor more coupling bores 216, each configured to receive a fastener (notshown) therethrough, such as a nut and bolt assembly, to facilitatecoupling the bonnet and stuffing box assembly 100 to the equipment. Inthe present aspect, the coupling bores 216 can be formed on a bonnetflange 218 distal from the stuffing box 150, as shown. In other aspects,the bonnet and stuffing box assembly 100 can be coupled to the equipmentby any other suitable fastener known in the art, including but notlimited to screws, welding, clips, adhesives, and the like.

FIG. 3 illustrates a cross-sectional view of the bonnet and stuffing boxassembly 100, taken along line 3-3 in FIG. 2. The bonnet 110 can definea bonnet bore 312, and the stuffing box 150 can define a stuffing boxbore 352. The bonnet bore 312 can be defined by a bonnet bore wall 314of the bonnet 110, and the stuffing box bore 352 can be defined by astuffing box bore wall 354 of the stuffing box 150. Example aspects ofthe bonnet bore 312 can generally define an upper bonnet bore portion316 and a lower bonnet bore portion 318, as shown. The upper bonnet boreportion 316 and the stuffing box bore 352 can be in facing engagementand can together define an assembly bore 320. The assembly bore 320 candefine a top bore end 322 and a bottom bore end 324, relative to theorientation shown. The top bore end 322 can be formed at a top end 356of the stuffing box 150. The bottom bore end 324 can be formed where theupper bonnet bore portion 316 meets the lower bonnet bore portion 318.

As shown, in example aspects, the stuffing box bore wall 354 can taperfrom the bottom end 254 of the stuffing box 150 towards the top bore end322, such that a substantially conical shape is defined. The bonnet borewall 314 can taper from the top end 214 of the bonnet 110 towards thebottom bore end 324, such that an inverted substantially conical shapeis defined by the upper bonnet bore portion 316. As such, the assemblybore 320 can define a diameter D₁ at a midpoint thereof that can begreater than a diameter D₂ at the top bore end 322 and a diameter D₃ atthe bottom bore end 324. In one example aspect, the bonnet 110 andstuffing box 150 can be formed from a ductile iron material, and thecorresponding bonnet bore wall 314 and stuffing box bore wall 354 can becoated or partially coated in an e-coating to protect from corrosion.

The stem 160 can be configured to extend fully through the assembly bore320. In the present aspect, a middle portion 362 of the stem 160 can bereceived in the stem bore, an upper portion 361 of the stem 160 canextend beyond the top bore end 322, and a lower portion 363 of the stem160 can extend beyond the bottom bore end 324. Example aspects of thestem 160 can define a stem flange 364 extending from the middle portion362, as shown. The op nut 170 can be attached to the upper portion 361of the stem 160 and can be configured to be engaged by a wrench or othertool to operate the stem 160. The lower portion 363 of the stem 160 candefine threading 366 for threaded engagement with a valve, such as, forexample, a gate valve. In other aspects, the stem 160 can define anysurface arrangement for use with any desired valve, such as a butterflyvalve, a check valve, and the like.

A bushing assembly 300 can be received in the assembly bore 320 and candefine a bushing bore 302 through which the stem 160 can extend. In thepresent aspect, the bushing assembly 300 can comprise a stuffing boxbushing 330 and a bonnet bushing 340. The stuffing box bushing 330 canbe substantially received in the stuffing box bore 352, and the bonnetbushing 340 can be substantially received in the upper bonnet boreportion 316. In some aspects, as shown, a portion of the stuffing boxbushing 330 can also engage the upper bonnet bore portion 316. An outerstuffing box bushing surface 332 of the stuffing box bushing 330 canengage the stuffing box bore wall 354, and an outer bonnet bushingsurface 342 of the bonnet bushing 340 can engage the bonnet bore wall314 within the upper bonnet bore portion 316. The stuffing box bushing330 can define a substantially conical shape similar to thesubstantially conical shape of the stuffing box bore 352, and the bonnetbushing 340 can define an inverted substantially conical shape similarto the upper bonnet bore portion 316. For example, the outer stuffingbox bushing surface 332 of the stuffing box bushing 330 can taperoutward from a first end 331 a thereof to a second end 331 b thereof,and the outer bonnet bushing surface 342 of the bonnet bushing 340 cantaper outward from a first end 341 a thereof to a second end 341 bthereof. When assembled, the second end 341 b of the bonnet bushing 340can confront the second end 331 b of the stuffing box bushing 330.

In the present aspect, as shown, the stuffing box bushing 330 and thebonnet bushing 340 can be substantially identical and can be symmetricalwhen installed in the bonnet and stuffing box assembly 100. However, inother aspects, such as the aspects illustrated in FIGS. 5 and 6, thestuffing box bushing 330 and bonnet bushing 340 can differ in shape andcan be asymmetrical when installed in the bonnet and stuffing boxassembly 100. Furthermore, example aspects of the stuffing box bushing330 and the bonnet bushing 340 can be formed from an material that isinherently corrosion-resistant and that can be precision-machined, suchas, for example, bronze or stainless steel, or can comprise acorrosion-resistant coating, such as, for example an e-coating, whichcan be applied by an electrophoretic painting process.

The stuffing box bushing 330 can define a stuffing box bushing bore wall334, and the bonnet bushing 340 can define a bonnet bushing bore wall344. The stuffing box bushing bore wall 334 and bonnet bushing bore wall344 can together define the bushing bore 302, as shown. According toexample aspects, each of the stuffing box bushing bore wall 334 and thebonnet bushing bore wall 344 can be precision-machined for optimalengagement with the middle portion 362 of the stem 160 to capture thestem flange 364 therebetween. In some aspects, the outer bonnet bushingsurface 342 and/or the outer stuffing box bushing surface 332 can alsobe precision-machined for optimal engagement with the bonnet 100 andstuffing box 150. In still other aspects, the entire bonnet bushing 340and/or the entire stuffing box bushing 330 can be precision-machined.

According to example aspects, each of the stuffing box bushing 330 andthe bonnet bushing 340 can define an annular indentation 303 formed inthe corresponding bushing bore walls 334,344, respectively. The annularindentations 303 of the stuffing box bushing 330 and bonnet bushing 340can together define an annular flange channel 304. The stem flange 364of the stem 160 can engage the annular flange channel 304 of the bushingassembly 300, as shown. In example aspects, the stem flange 364 can beardown on the bonnet bushing 340 at the annular indentation 303, which canaid in properly seating the bushing assembly 300 in the assembly bore320. As shown, in example aspects, a clearance can be provided betweenthe stem flange 364 and the annular flange channel 304, such that thestem flange 364 is not tightly received in the annular flange channel304 and the stem 160 can easily rotate within the bushing bore 302.

Example aspects of the stem 160 can define one or more circumferentialstem grooves 370 formed in an outer stem surface 368 of the stem 160.For example, as shown, in one aspect, a first stem groove 370 a can beformed proximate the bottom bore end 324 of the assembly bore 320 and asecond stem groove 370 b can be formed proximate the top bore end 322 ofthe assembly bore 320. A third stem groove 370 c can be formed betweenthe stem flange 364 and the first stem groove 370 a, and fourth andfifth stem grooves 370 d,370 e can be formed between the stem flange 364and the second stem groove 370 b. In other aspects, any number of stemgrooves 370 can be formed at any suitable location along the middleportion 362 of the stem 160.

In the present aspect, each of the stem grooves 370 a-e can beconfigured to receive a packing (not shown), such as, for example, anO-ring. For example, a primary O-ring (not shown) can be received in thefirst stem groove 370 a to create a seal between the stem 160 and thebonnet 110. A secondary O-ring 371 c (not shown) can be received in thethird stem groove 370 c to create a seal between the stem 160 and thebonnet bushing 340, and additional secondary O-rings 371 d,371 e can bereceived in the fourth and fifth stem grooves 370 d,370 e, respectivelyto create seals between the stem 160 and the stuffing box bushing 330.Each of the seals created by the primary O-rings and secondary O-rings371 c,d,e can prohibit or minimize fluid flow past the seals.Furthermore, each of the primary O-rings and secondary O-rings 371 c,d,ereceived in the stem grooves 370 a-e can allow the stem 160 to rotaterelative to the bushing assembly 300, the bonnet 110, and the stuffingbox 150, while maintaining a watertight seal with each of the theseelements. In other aspects, the stem grooves 370 can be located on thebushing assembly 300, the bonnet 110, and/or the stuffing box 150,provided that their positioning allows for creating a watertight sealwith the stem 160.

A protective O-ring (not shown) can be received in the second stemgroove 370 b and can create a seal between the stem 160 and the stuffingbox 150 at the top end 356 of the stuffing box 150. In some aspects, theprotective O-ring can prevent undesirable external elements (e.g.,ground water, silt, sand) from entering the assembly bore 320 and/orbushing bore 302 through the top end 356 of the stuffing box 150. Inother aspects, a dirt seal mechanism can be provided for preventingundesirable elements from entering the bonnet and stuffing box assembly100. In one aspect, the direct seal mechanism can be snapped onto theupper portion 361 of the stem 160 at the top end 356 of the stuffing box150 and can cover the top bore end 322 of the assembly bore 320. In aparticular aspect, for example, the dirt seal can define a generallyumbrella-shaped cap.

The bonnet bushing 340 can define a circumferential bonnet bushinggroove 346 formed in the outer bonnet bushing surface 342 thereof, andthe stuffing box bushing 330 can define a circumferential stuffing boxbushing groove 336 formed in the outer stuffing box bushing surface 332thereof. Each of the bonnet bushing 340 and stuffing box bushing 330 canalso define an annular chamfer 305 formed in the corresponding outerbonnet bushing surface 342 and outer stuffing box bushing surface 332.The annular chamfers 305 together can form an annular notch 306. Apacking (not shown), such as another secondary O-ring 347, can bereceived in the bonnet bushing groove 346 to create a seal between thebonnet bushing groove 346 and the bonnet bore wall 314. A secondaryO-ring 307 (not shown) can also be received in the annular notch 306 tocreate a seal between the bushing assembly 300 and the bonnet bore wall314. Each of the seals can prevent or minimize fluid flow past the seal.

In some aspects, a packing (not shown) can be received in the stuffingbox bushing groove 336 to create a seal between the outer stuffing boxbushing surface 332 and the stuffing box bore wall 354. However, inother aspects, it may not be necessary to create a seal between theouter stuffing box bushing surface 332 and the stuffing box bore wall354 at the location of the stuffing box bushing groove 336.

As such, fluid received in the lower bonnet bore portion 318 can beprevented from entering the assembly bore 320 by the primary O-ring, orother packing, received in the first stem groove 370 a proximate thebottom bore end 324 of the assembly bore 320. In the event that the sealprovided by the primary O-ring fails and fluid enters the assembly bore320, the secondary O-rings 371 c-e received in the third, fourth, andfifth stem grooves 370 c-e, respectively, can prevent the fluid fromprogressing further through the bushing bore 302, and the secondaryO-rings received in the bonnet bushing groove 346 and annular notch 306(and, if present, the secondary O-ring received in the stuffing boxbushing groove 336) can prevent the fluid from progressing furtherthrough the assembly bore 320 around the bushing assembly 300. In someaspects, if fluid passes the O-ring formed in the annular notch 306, thefluid can exit through the gap 190 between the bonnet 110 and stuffingbox 150.

FIG. 4 illustrates an exploded view of the bonnet and stuffing boxassembly 100. In one aspect, a method for using the bonnet and stuffingbox assembly 100 can comprising providing the stuffing box 150, thebonnet 110, the bushing assembly 300, and the stem 160, wherein thestuffing box 150 and bonnet 110 define the assembly bore 320 (shown inFIG. 3) within which the bushing assembly 300 can be received, thebushing assembly 300 defines the bushing bore 302 (shown in FIG. 3), andthe stem 160 is received through the bushing bore 302 and the assemblybore 320. The method can further comprise sealing the stem 160 relativeto the bushing assembly 300 to prohibit fluid flow through the bushingbore 302 and sealing the bushing assembly 300 relative to the bonnet 110to prohibit fluid flow through the assembly bore 320, such as byinstalling the primary and secondary O-rings 371 c-e, 307,347 (shown inFIG. 3) previously described. Finally, the method can comprise turningthe stem 160 relative to the bushing assembly 300, bonnet 110, andstuffing box 150 to actuate a valve. Example aspects of turning the stem160 can comprise engaging the op nut 170 with a tool (not shown) androtating the op nut 170 with the tool. Further example aspects ofturning the stem 160 can comprise turning the threading 366 to translatea gate valve. In some aspects, the method can further comprise pressingthe stem flange 364 of the stem 160 against the bushing assembly 300 toseat the bushing assembly 300 in the assembly bore 320.

FIG. 5 illustrates the bonnet and stuffing box assembly 100 according toanother aspect, wherein the bonnet bushing 340 and the stuffing boxbushing 330 can differ from one another and can be asymmetrical wheninstalled in the bonnet and stuffing box assembly 100. While differingin shape, the stuffing box bushing 330 and bonnet bushing 340 of thepresent aspect can function substantially similarly to the identicalstuffing box bushing 330 and bonnet bushing 340 of FIGS. 1-4. Onenotable difference is that, in the present aspect, a sixth stem groove570 can be formed in the annular flange channel 304 of the bushingassembly 300. A packing (not shown), such as an O-ring, can be receivedtherein to form a seal between the stem 160 and the bushing assembly 300at the location of the stem flange 364. Another difference is that thesecond stem groove 370 b can be formed in the stuffing box bushing borewall 334 of the stuffing box bushing 330, instead of in the outer stemsurface 368 of the stem 160.

Also in the present aspect, a dirt seal 510 can be formed at a top end502 of the bushing assembly 300 proximate the top bore end 322 (shown inFIG. 3) of the assembly bore 320. The dirt seal 510 can serve toprohibit undesirable external elements from entering the assembly bore320 and/or bushing bore 302 through the top bore end 322 of the assemblybore 320. Example aspects of the dirt seal 510 can be configure tooverhang the second stem groove 370 b, as shown, and can extend betweenthe stem 160 and the stuffing box 150, such that the top bore end 322 ofthe assembly bore 320 is completely covered.

FIG. 6 illustrates still another aspect of the bonnet and stuffing boxassembly 100, wherein the bonnet bushing 340 and the stuffing boxbushing 330 can differ from another and can be asymmetrical wheninstalled in the bonnet and stuffing box assembly 100. The stuffing box150, bonnet 110, and bushing assembly 300 are shown in cross-section,such that the outer stem surface 368 of the stem 160 is visible. Whilediffering in shape, the stuffing box bushing 330 and bonnet bushing 340of the present aspect can function substantially similar to theidentical stuffing box bushing 330 and bonnet bushing 340 of FIGS. 1-4.One notable difference, however, is that, in the present aspect, abushing groove 610 can be formed between the stuffing box bushing 330and the bonnet bushing 340 when the bushing assembly 300 is assembled. Apacking (not shown), such as an O-ring, can be received in the bushinggroove 610 to create a seal between the stuffing box bushing 330 and thebonnet bushing 340.

One should note that conditional language, such as, among others, “can,”“could,” “might,” or “may,” unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements and/or steps. Thus, suchconditional language is not generally intended to imply that features,elements and/or steps are in any way required for one or more particularembodiments or that one or more particular embodiments necessarilyinclude logic for deciding, with or without user input or prompting,whether these features, elements and/or steps are included or are to beperformed in any particular embodiment.

It should be emphasized that the above-described embodiments are merelypossible examples of implementations, merely set forth for a clearunderstanding of the principles of the present disclosure. Any processdescriptions or blocks in flow diagrams should be understood asrepresenting modules, segments, or portions of code which include one ormore executable instructions for implementing specific logical functionsor steps in the process, and alternate implementations are included inwhich functions may not be included or executed at all, may be executedout of order from that shown or discussed, including substantiallyconcurrently or in reverse order, depending on the functionalityinvolved, as would be understood by those reasonably skilled in the artof the present disclosure. Many variations and modifications may be madeto the above-described embodiment(s) without departing substantiallyfrom the spirit and principles of the present disclosure. Further, thescope of the present disclosure is intended to cover any and allcombinations and sub-combinations of all elements, features, and aspectsdiscussed above. All such modifications and variations are intended tobe included herein within the scope of the present disclosure, and allpossible claims to individual aspects or combinations of elements orsteps are intended to be supported by the present disclosure.

1. A bushing assembly for a bonnet and stuffing box assembly comprising:a stuffing box bushing, the stuffing box bushing defining an outerstuffing box bushing surface and a stuffing box bushing bore wall, theouter stuffing box bushing surface defining a substantially conicalshape, the stuffing box bushing bore wall defining a first annularindentation; a bonnet bushing, the bonnet bushing defining an outerbonnet bushing surface and a bonnet bushing bore wall, the outer bonnetbushing surface defining a substantially conical shape, the bonnetbushing bore wall defining a second annular indentation, the bonnetbushing bore wall and the stuffing box bushing bore wall togetherdefining a bushing bore, and the first annular indentation and thesecond annular indentation together defining a flange channel; and astem extending through the bushing bore, the stem defining a stemflange, the stem flange engaging the flange channel.
 2. The bushingassembly of claim 1, wherein the stuffing box bushing and the bonnetbushing are substantially identical in size and in shape.
 3. The bushingassembly of claim 1, wherein; the bonnet bushing defines an annularchamfer; the stuffing box bushing defines an annular chamfer; theannular chamfer of the bonnet bushing and the annular chamfer of thestuffing box bushing together define an annular notch; and the annularnotch is configured to receive a packing.
 4. (canceled)
 5. The bushingassembly of claim 1, wherein the outer bonnet bushing surface defines acircumferential bonnet bushing groove configured to receive a packing.6. The bushing assembly of claim 1, wherein; the outer bonnet bushingsurface tapers from a first end of the bonnet bushing to a second end ofthe bonnet bushing; the outer stuffing box bushing surface tapers from asecond end of the stuffing box bushing to a first end of the stuffingbox bushing; and the second end of the bonnet bushing confronts thesecond end of stuffing box bushing.
 7. The bushing assembly of claim 1,wherein each of the stuffing box bushing bore wall and the bonnetbushing bore wall are precision-machined.
 8. The bushing assembly ofclaim 1, further defining a stem groove formed in one of the bonnetbushing bore wall and the stuffing box bushing bore wall, the stemgroove configured to receive a packing.
 9. A bonnet and stuffing boxassembly comprising: a bonnet comprising a bonnet bore wall, the bonnetbore wall defining a bonnet bore, the bonnet bore defining asubstantially conical shape; a stuffing box connected to the bonnet, thestuffing box defining a stuffing box bore, the stuffing box boredefining a substantially conical shape, the stuffing box bore and bonnetbore defining an assembly bore; a bushing assembly received in theassembly bore and extending from the bonnet bore into the stuffing boxbore, the bushing assembly defining a bushing bore and comprising abonnet bushing and a stuffing box bushing, wherein an outer bonnetbushing surface of the bonnet bushing engages the bonnet bore wall; afirst packing received between the bonnet bushing and the bonnet borewall; and a stem extending through the bushing bore and defining a stemflange engaging a flange channel of the bushing assembly.
 10. The bonnetand stuffing box assembly of claim 9, wherein; at least a portion of thebonnet bushing is received in the bonnet bore; and at least a portion ofthe stuffing box bushing is received in the stuffing box bore.
 11. Thebonnet and stuffing box assembly of claim 10, wherein the bonnet bushingdefines a precision-machined bonnet bushing bore wall, and the stuffingbox bushing defines a precision-machined stuffing box bushing bore wall.12. The bonnet and stuffing box assembly of claim 9, wherein thestuffing box and the bonnet are manufactured by a casting process. 13.(canceled)
 14. The bonnet and stuffing box assembly of claim 13, whereinthe stem flange bears down upon the bushing assembly to seat the bushingassembly against the bonnet bore wall.
 15. The bonnet and stuffing boxassembly of claim 9, wherein at least one of the bushing assembly andthe stem defines a stem groove configured to receive a second packing tocreate a watertight seal between the stem and the bushing assembly. 16.The bonnet and stuffing box assembly of claim 9, wherein at least one ofthe bonnet bushing and the bonnet bore wall defines a bushing grooveconfigured to receive the first packing to create a watertight sealbetween the bushing assembly and the bonnet.
 17. The bonnet and stuffingbox assembly of claim 9, further comprising a dirt seal configured tocover a top end of the assembly bore.
 18. A method for using a bonnetand stuffing box assembly comprising: providing a stuffing box, abonnet, a bushing assembly, and a stem, the stuffing box and bonnetdefining an assembly bore, the bushing assembly received in the assemblybore, the bushing assembly defining a bushing bore and comprising abonnet bushing and a stuffing box bushing, and the stem received throughthe bushing bore, wherein a stem flange of the stem engages a firstannular indentation of the stuffing box bushing and a second annularindentation of the bonnet bushing; sealing the stem relative to thebushing assembly to prohibit fluid flow through the bushing bore;sealing the bushing bore assembly relative to the bonnet to prohibitfluid flow through the assembly bore; pressing the stem flange againstthe bonnet bushing at the second annular indentation to seat the bushingassembly in the assembly bore; and turning the stem relative to thebushing assembly, bonnet, and stuffing box to actuate a valve.
 19. Themethod of claim 18, further comprising pressing the stem flange of thestem against the bushing assembly to seat the bushing assembly in theassembly bore.
 20. The method of claim 18, wherein turning the stemrelative to the bushing assembly, bonnet, and stuffing box to actuate avalve comprises engaging an operating nut with a tool and rotating theoperating nut with the tool.